If you're looking for a specific download link, I can suggest some possible sources:
: Insert the card into your powered-off TV box. Use a toothpick to hold down the hidden Reset button (often inside the AV port) and connect the power. Release the button when the upgrade screen or "green robot" appears on your TV.
: Format a micro-SD card to FAT32 with a single partition. Configuration : Run Burn_Card_Maker.exe . Select your SD card from the disk list.
Do you have the of your TV box so I can help you find the correct firmware?